The air we breathe contains varying amounts of particles such as dust, dirt pollen, smog and noxious fumes. Air pollution is fast becoming one of the largest health threats of the industrial world. Lung cancer and cardiovascular disease are increasing because of factory and vehicle air pollution where recent studies have shown lung cancer is two to three times more common in cities than in the countryside despite similar rates of tobacco smoking. Workers in certain industrial or agricultural operations are exposed to toxic dusts, mists and fumes which can cause illness or death even if inhaled in relatively small quantities over a period of time.
Many persons, because of their jobs, lifestyle or location, must expose themselves to airborne particulate matter or fumes that are allergenic, or which can be injurious to their health. The size of the particles is a main determinant of where in the respiratory tract the particle will come to rest when inhaled. Larger particles are generally filtered in the nose and throat via cilia and mucus, but particulate matter smaller than about 10 micrometres, referred to as PM10, can settle in the bronchi and lungs and cause health problems. The 10 micrometre size does not represent a strict boundary between respirable and non-respirable particles, but has been agreed upon for monitoring of airborne particulate matter by most regulatory agencies. Because of their small size, particles in the order of ˜10 micrometres or less (PM10) can penetrate the deepest part of the lungs such as the bronchioles or alveoli.
Similarly, so-called fine PM, particles smaller than 2.5 micrometres, PM2.5, tend to penetrate into the gas exchange regions of the lung (alveolus), and very small particles (<100 nanometres) may pass through the lungs to affect other organs.
Some persons are allergic to certain pollens or dust occurring naturally in the air and manifest this by an allergic reaction known as Hay Fever. Quite often, if uncontrolled, this allergic reaction progresses to a serious sinus condition or asthma. Also, the purity or quality of air may be affected by the presence of infectious airbourne contaminates.
Face masks are used to combat air pollution and contaminates that affect the quality of air. A conventional face mask is usually manufactured out of a piece of material that aims to filter out particulate material and seals or contacts against the face. One example is a mask that is manufactured out of cotton material, with lots of leakage around the face and within the mask, the filter either being just a tiny square inside the cotton mask or the entire mask itself. Nevertheless these types of mask are not particularly effective at filtering out particulate matter. Furthermore, these types of mask may only address air particulates and not noxious gases. Also, as the mask contacts the face, this is uncomfortable for a wearer and some skin types are sensitive to conventional mask material and extended use can create skin irritation and even skin damage. Even users with non-sensitive skin may develop skin irritations from face mask contact.
A mask that contacts the face of a user with facial hair can not form an effective seal due the facial hair forming a barrier between the mask and skin contact surface. In fact, a study on the effect of facial hair on the face seal of negative-pressure respirators has shown at least a 330 fold drop in protection of a dust mask when used with a beard. Results such as this indicate that the presence of a beard greatly increases the leakage through the respirator face seal, and this leakage should not be permitted when users are required to wear respirators. Furthermore, wearing a conventional mask makes communication difficult both audibly and visually.
Style is also a consideration for a wearer and some prior art masks are bulky and those considered to be unaesthetically pleasing to the eye are less likely to be worn.
Conventional respiratory filter masks are often worn by people who are exposed to airborne particulate matter or noxious gases or fumes to avoid inhaling these harmful substances. In order to achieve an effective efficiency and an unencumbering resistance to airflow, conventional respiratory filter masks are cumbersome and of a design that makes them impractical for everyday use. For example, wearing one of these face mask filters is very uncomfortable with necessarily tight-fitting head straps and face mask seals. Notwithstanding that, all people's faces are different in shape making it difficult to achieve a positive seal with the prior art models. In addition, the wearer of one of these masks must forcefully inhale against the pressure drop of the air passing through the filter media and when exhaling must force the air out through an exhaust valve. After a period of time this can become uncomfortable to normal people and exhausting to those with respiratory problems.
Full face coverage filter masks that do cover the eyes in addition to nose and mouth are often prone to fogging of the transparent face shield and are even more uncomfortable to wear. As above, speech and sight are greatly impaired and bulky hoses and filter cartridges are cumbersome and unsightly to wear. In fact prior art face mask filter respirators are so cumbersome and uncomfortable that many people (including allergy suffers) risk the health hazards involved rather than wear this type of protection.
From the above, it can be seen that there is a need for an improved flow or face mask that overcomes disadvantages of known face masks or at least provides the public with a useful choice.
Further aspects and advantages of the process and product will become apparent from the ensuing description that is given by way of example only.